'\" t
.\" Copyright (c) 2008 Linux Foundation, written by Michael Kerrisk
.\"     <mtk.manpages@gmail.com>
.\"
.\" SPDX-License-Identifier: Linux-man-pages-copyleft
.\"
.TH pthread_setschedprio 3 2024-05-02 "Linux man-pages 6.9.1"
.SH NAME
pthread_setschedprio \- set scheduling priority of a thread
.SH LIBRARY
POSIX threads library
.RI ( libpthread ", " \-lpthread )
.SH SYNOPSIS
.nf
.B #include <pthread.h>
.P
.BI "int pthread_setschedprio(pthread_t " thread ", int " prio );
.fi
.SH DESCRIPTION
The
.BR pthread_setschedprio ()
function sets the scheduling priority of the thread
.I thread
to the value specified in
.IR prio .
(By contrast
.BR pthread_setschedparam (3)
changes both the scheduling policy and priority of a thread.)
.\" FIXME . nptl/pthread_setschedprio.c has the following
.\"   /* If the thread should have higher priority because of some
.\"      PTHREAD_PRIO_PROTECT mutexes it holds, adjust the priority. */
.\" Eventually (perhaps after writing the mutexattr pages), we
.\" may want to add something on the topic to this page.
.\" nptl/pthread_setschedparam.c has a similar case.
.SH RETURN VALUE
On success, this function returns 0;
on error, it returns a nonzero error number.
If
.BR pthread_setschedprio ()
fails, the scheduling priority of
.I thread
is not changed.
.SH ERRORS
.TP
.B EINVAL
.I prio
is not valid for the scheduling policy of the specified thread.
.TP
.B EPERM
The caller does not have appropriate privileges
to set the specified priority.
.TP
.B ESRCH
No thread with the ID
.I thread
could be found.
.P
POSIX.1 also documents an
.B ENOTSUP
("attempt was made to set the priority
to an unsupported value") error for
.BR pthread_setschedparam (3).
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.TS
allbox;
lbx lb lb
l l l.
Interface	Attribute	Value
T{
.na
.nh
.BR pthread_setschedprio ()
T}	Thread safety	MT-Safe
.TE
.SH STANDARDS
POSIX.1-2008.
.SH HISTORY
glibc 2.3.4.
POSIX.1-2001.
.SH NOTES
For a description of the permissions required to, and the effect of,
changing a thread's scheduling priority,
and details of the permitted ranges for priorities
in each scheduling policy, see
.BR sched (7).
.SH SEE ALSO
.ad l
.nh
.BR getrlimit (2),
.BR sched_get_priority_min (2),
.BR pthread_attr_init (3),
.BR pthread_attr_setinheritsched (3),
.BR pthread_attr_setschedparam (3),
.BR pthread_attr_setschedpolicy (3),
.BR pthread_create (3),
.BR pthread_self (3),
.BR pthread_setschedparam (3),
.BR pthreads (7),
.BR sched (7)
